An Analysis of H-Infinity Control for Offshore Wind Turbines

Abstract

Abstract Conventional wind turbine (WT) pitch control is executed using traditional methods, generally based on proportional-integral-derivative (PID) controllers. Although reaching satisfactory power regulation and robust behavior, this approach does not explicitly consider the reduction of mechanical loads on the WT structure. In fact, the active pitch control can be used to influence the WT structural response as an auxiliary objective for mitigating loads and increasing the WT reliability, diminishing O&M costs. This is even more relevant for offshore WTs, where difficulties of maintenance impose the need for technologies that enable longer useful life of components. In this paper, we present the application of an advanced control method, the H-infinity, to change the conventional pitch control and include loading reductions as an explicit control objective.